The invention concerns a device designed and adapted for electrical muscle stimulation of muscles involved in the physiological gait of a human, comprising an element for electrical muscle stimulation, a sensor for detecting information relevant to the muscle stimulation, and a control and/or regulation unit for triggering the muscle stimulation on the basis of the information detected by the sensor.
The invention furthermore concerns an orthosis, or brace, designed and adapted for supporting at least the anatomical lower leg of a human, comprising a lower leg support element and a foot support element connected to the lower leg support element.
The invention also concerns a method for electrical muscle stimulation of muscles involved in the physiological gait of a human, by means of a device for muscle stimulation, comprising. the steps: determining a switching time for the muscle stimulation by means of a sensor, transmitting the switching time to a control and/or regulation unit, triggering the muscle stimulation by the control and/or regulation unit on the basis of the information detected by the sensor, and stimulating muscles by means of an element for electrical muscle stimulation.
Such devices and methods are used in particular in orthopedics in order to achieve a stimulation of the muscles involved in the physiological gait of a human in patients with a muscle and/or joint and/or bone weakness, for example because of a stroke or a paraplegia or other disorder adversely affecting the gait of a human. The orthosis joints are used in particular in patients with a chronic disease, for patients during therapy and as a walking or standing aid for patients with weakened or contracted musculature.
A plurality of muscles or muscle groups are involved in the physiological gait of the human. Purely as an example, these include the calf muscles, the trunk muscles, the buttock muscles and also the arm muscles. In known illness patterns, for example following a stroke, control of the muscle by the brain via the respective nerve pathways is disrupted. This means that the muscles can fully or partly no longer be controlled. This effect necessarily leads to a muscular atrophy of the muscles which are no longer controlled and therefore no longer involved in the physiological gait. For example with a stroke, as a result a so-called flaccid paralysis can occur. Spasticity can also occur. Both flaccid paralysis and spasticity, due to lack of control and corresponding lack of activity, lead to atrophy of the muscles concerned. Thus walking, for example supported by an orthosis, becomes ever more difficult and unsafe for the people concerned. In other words, the natural gait or individual walking phases of a walk cycle may no longer be supported, or only within limitations. In particular, muscular atrophy leads to a deteriorating condition and consequently an unsafe gait. Due to the loss of control of the muscles or muscle fibers, individual phases of the gait, e.g. the push-off phase during walking, are not supported, whereby a defective gait results.
In principle, it is known to stimulate electrically the weakened muscles and/or muscles no longer controlled. For this bandages or stockings are known. These bandages/stockings known from the trade, as elements for electrical muscle stimulation, normally serve to stimulate the foot-lifting muscles to lift the feet during the swing phase. The relevant information detected by the sensor is in particular the time of muscle stimulation. ‘To trigger the electrical muscle stimulation, a signal from a pressure sensor as a sensor is used, which transmits the signal via a cable to a control and/or regulation unit. The pressure sensor is arranged below the foot and normally fitted in the patient's shoe. The muscle stimulation is triggered at a pressure level to be determined. The problem with the known solution lies in determining the correct pressure. Because the pressure sensor is carried in a shoe, the problem exists that the shoe is laced up sometimes more tightly and sometimes less tightly, which has a direct effect on the pressure and hinders the determination of a precisely defined time of muscle stimulation. On the one hand, pressure is applied permanently to the pressure sensor. On the other hand, pressure is determined by the pressure sensor below the foot over almost the entire standing phase which accounts for around 60% of the walking cycle, whereby determination of an optimal time of muscle stimulation is imprecise. A further disadvantage is that because of the problem of space below the foot, the signal from the pressure sensor is transmitted by means of a wire to the control and/or regulation unit. This configuration makes handling more difficult and is susceptible to damage. Also, a temporally incorrect and/or overly intensive (over-long) muscle stimulation is perceived by the patient as disruptive or uncomfortable.